The proposed work will lead to elucidation to the mechanism of enzymatic activation of indicine N-oxide, an antitumor agent with unique structure and with potential alkylating capacity of an unusual type, and to clearer concepts of its mechanism of action and of processes involved in its detoxification. Identification of a new class of alkylating agents would allow clinicians another alternative in selecting drugs for cancer chemotherapy. The work involves chemical synthesis of radioactive-labeled indicine N-oxide and related compounds and utilization of the labeled compounds in enzymatic systems to determine the processes involved in their activation and detoxification. The binding of activated products to sulfhydryl compounds. proteins, and nucleic acids in vitro and to proteins and nucleic acids in intact animals will be investigated. Since indicine N-oxide has been recently selected for clinical trial, activated products will be evaluated as toxic and antitumor agents.